Originally prototype series 400. First flew in 1965. Converted to series 500 prototype in 1967, series 475 prototype in 1970 and series 670 prototype in 1977. Later converted back to a series 475. To Brooklands Museum in 1994.

Ex-Series 400AM, converted to the Series 500 prototype February-June 1967. Subsequently became the Series 475 prototype and the Series 670 prototype, then converted back to Series 475AM. On display at Brooklands Museum in 2020.